1. Field of the Invention
The invention relates to wireless local are network (WLAN), and more particularly, to systems for WLAN transmission with reduced power consumption and for the coexistence of WLAN and another type of wireless transmission (e.g. Bluetooth, WiMAX or others) with higher download rates.
2. Description of the Related Art
Wireless local area network (WLAN) modules embedded in mobile electronic devices such as notebooks, cellular phones, portable gaming devices, portable multimedia players, global positioning system (GPS) receivers, or others, are used to wirelessly connect to the Internet for browsing Web pages, transceiving e-mails, chatting on-line, downloading and playing multimedia content, or others. Since mobile electronic devices typically provide limited battery power, extending the battery life thereof is an essential technical goal for those skilled in the art. Thus, decreasing power consumption of embedded WLAN modules may extend usage life of mobile electronic devices thereof.
Mobile electronic devices, are increasingly, not only equipped with WLAN modules but also Bluetooth, WiMAX modules, or others to enhance connectivity thereof, to various peer devices or the Internet. Because both WLAN and Bluetooth/WiMAX wireless technology share spectrum and are typically located in close physical proximity to one another when operating, interference therebetween may occur if transmission or receiving time slots are not appropriately scheduled. The lengths of the time slots assigned to the WLAN module typically vary with the bandwidth requirement of the Bluetooth and/or WiMAX module(s). Thus, efficient and flexible utilization of the assigned windows to receive buffered data from an access point or station so as to consume less power, reduce interference possibility with the other WLAN devices, or others, is also important for the coexistence of the WLAN and Bluetooth/WiMAX.